ML20071H936

Final Significant Deficiency Rept SD 370/81-12 Re Butt Welds Not Meeting ASME Code Criteria.Const Procedure Will Be Generated 820401 to Define Properties of Worse Case Weld. Future Flush Welds to Be Compared to Established Properties

ML20071H936
Person / Time
Site:	Mcguire
Issue date:	02/22/1982
From:	Parker W DUKE POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
10CFR-050.55E, 10CFR-50.55E, NUDOCS 8203080584
Download: ML20071H936 (3)

Text

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DUKE POWEH COMI%NY l'owru llCllDING 4e2 SouTu Cnt:ucu Srnrer, CHAHInTTE, N. C. 2a242 WI L LI AM O. PA R M E R. J R.

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Mr. James P. O'Reilly, Regional Administrator og 'm U. S. Nucicar Regulatory Commission e 9 o ph Region II g -

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101 Marietta Street, Suite 3100 g 6 g,,y -

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Atlanta, Georgia 30303 - c.n n .

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Re: McGuire Nuclear Station 9" Mi!R 0 51982> ~

Unit 2 IBM *WN N sguan onzm1It /p

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Docket No. 50-370 g Tic

Dear Mr. O'Reilly:

co Pursuant to 10 CFR 50.55e, please find attached Significant Deficiency Report SD 370/81-12 (final) concerning butt welds that may not meet ASME Code criteria for being " flush". An interim report was submitted by my letter dated January 21, 1982. This was also reported for Unit i via LER 369/81-192.

Ve/ytrulyyours,'

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William 0. Parker,.Jr.

PBN/j fw Attachment cc: (w/ attachment)

Director Mr. P. R. Bemis Office of Inspection and Enforcement NRC Resident Inspector U. S. Nuclear Regulatory Commission McGuire Nuclear Station Washington, D. C. 20555 Mr. Ralph Birkel Division of Project Management Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555 0FFICIM. COPY B203000504 820222

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DUKE POWER COMPANY McGUIRE NUCLEAR STATION SIGNIFICANT DEFICIENCY REPORT N0.: SD 370/81-12 (final)

REPORT DATE: February 22, 1982 FACILITY: McGuire Nuclear Station, Unit 2 IDENTIFICATION OF DEFICIENCY:

Welds identified as " flush" may not meet the stringent requirements of the ASME Code criteria as defined in Table NB-3683.2-1, footnote (2)(a).

Specifically, the requirement that the finished contour of the weld shall not exceed a 7 slope had not been satisfied at the weld I.D.

INITIAL REPORT:

The initial report was made to Mr. A. Ignatonis of Region II, USNRC, on December 22, 1981 by Mr. W. O. Henry and Mr. J. N. Underwood, both of Duke Power Company, 422 S. Church Street, Charlotte, NC 28242.

DESCRIPTION OF DEFICIENCY:

The initial deficiency was first identified by a Catawba Nuclear Station NCI which reported that certain butt welds did not meet the ASME Code criteria for being flush as defined in Table NB-3683.2-1. This NCI specifically pointed out that the I.D. of the weld did not meet the 7' contour as stipulated in footnote (2)(a) of that table. Furthermore, a review determined that the Catawba Construction procedure for flush welds may not provide adequate assurance that the weld contour on the I.D. is

<7. A review of the correspoading McGuire Nuclear Station procedure Indicates that similar conditions exist for McGuire flush welds.

ANALYSIS OF SAFETY IMPLICATIONS:

The stress analysis calculations generally employ the procedures outlined i in NB-3600 to ensure piping system integrity for all loading conditions.

! If the welds in question had been found not to satisfy the ASME Code requirements associated with flush welds, certain stress indices used in the piping analysis would be incorrect and of a lower value than those l associated with the as-welded condition. However, Duke reviewed a number

! of welds which were made using existing flush welding procedures to determine I

the " worst case" I.D. profile and analyzed them to determine the stress indices using stringent procedures outlined in the ASME Code. This analysis verified that Duke flush weld indices are equivalent to the ASME flush weld indices.

l Therefore, the existing piping analysis calculations remain valid and the lower indices used are correct.

' Duke Power Company McGuire Nuclear Station

. . . Significant Deficiency Page 2 CORRECTIVE ACTION:

A construction procedure will be generated on or before April 1,1982 to define a Duke Power flush weld as those with the properites of the " worst case" weld used in the previously described analysis. All future flush welds will be compared to these properties.

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